JPS61206861A - Tension regulator for belt in driving system of belt and driving belt car - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION The present invention relates generally to belt and pulley drive mechanisms, and more particularly to improved S! Regarding location.

Belt and pulley drive mechanisms have long been used in coupling a drive shaft, such as the shaft of an electric motor or other prime mover, to a driven shaft, such as the shaft of a generator, fan or pump. In each of these applications, the drive and driven shafts are commonly journalled for rotation by bearings or bushings. Appropriate tension is necessary to prevent the belt from slipping.
Although the tension needs to be maintained in the belt simply connecting the drive belt pulley, the tension need not be too great, i.e. the life of the bearing/bushing will be significantly reduced. Therefore, there is a need by which the tension of a belt or other flexible endless belt can be easily adjusted.

For purposes of example only and without intended limitation, the invention will be discussed with respect to its use in driving a centrifugal pump. However, it should be understood that the same approach may be used in a variety of other applications.

U.S. Pat. ．．
No. 863,517 discloses a belt tensioning installation in which the drive belt pulley is installed to be driven by the power take-off of an agricultural tractor, while the follower is connected to the shaft of a centrifugal pump. In this installation, the drive belt sheave has a first hole extending inwardly on one side of its hub that accommodates the output shaft of the motor, and a journal journal bearing for the drive belt sheave on the first end of the stub shaft. The hub has a second or opposite hole extending inwardly from the opposite side of the hub that accommodates the thrust bearing used to carry the thrust bearing. The bracket is bolted to the pump and has a hole that receives the other end of the stub shaft. The two ends of the stub shaft are juxtaposed with a predetermined eccentricity. A device is provided for adjusting the radial position of the stub shaft within the hole in the bracket. As the stub shaft is rotated in one direction or the other, eccentricity adds to or subtracts from the nominal spacing between the drive shaft and the shaft of the driven centrifugal pump.

The present invention is believed to be an improvement over the prior art pointed out by the aforementioned patent no. 3,863,517. Although the equipment disclosed in that aforementioned patent is fully operational and capable of achieving the objects and advantages described in that patent, it is relatively expensive to manufacture and Proves to be slightly more difficult to repair and maintain. For example, the previous Pare
The tensioning equipment shown in the J.A. '517 patent requires an eccentric stub shaft that is relatively expensive to construct. Also, rather than a conventional pulley, the previous device requires that the pulley have an inverted hole to accommodate the thrust bearing that supports the stub shaft. The tightening mechanism for the belt tension lever, which includes a slotted cup housing and an associated adjustable tightening lever, also provides an even more costly approach. Presently shown approaches to belt tension are particularly
provides numerous advantages over the prior art beyond those disclosed by the '517 patent. For example, many centrifugal pumps in use today require that the power takeoff (PTO) drive attachment be disassembled in order to remove the pump for repair.

However, with the mounting and belt tensioning equipment of the present invention, the pump can be separated from the PTO drive connection by removing only a single bolt.

It has been found that the tensioning equipment of the present invention provides low bearing loads and high resistance to slipping with little or no chatter or pickup. Additionally, the structure of the present invention is intended to be lighter and more compact without sacrificing the useful life of the assembly and its components.

Accordingly, a primary object of the present invention is to provide new and improved equipment for adjusting and maintaining tension in endless belts in belt and pulley systems.

Other objects of the invention provide the advantages of lower manufacturing costs, easier adjustment, higher reliability and greater ease of repair and maintenance than hitherto available and used prior art techniques. An object of the present invention is to provide an improved belt tensioning facility.

SUMMARY OF THE INVENTION The foregoing features and advantages of the present invention provide that a conventional drive belt pulley has a journal shaft for rotation in a laterally extending cylindrical hole formed through a rigid arm member at a first end thereof. Due to its mounted concept on supported symmetrical stepped shafts.

The opposite ends of the arms have a further cylindrical shape adapted to fit over the cylindrical curved hub portion of the case or housing of the machine to be driven, which, as mentioned above, is a typical centrifugal pump. It has a hole. Inside this hub is a conventional bearing that supports the shaft to which the pump impeller is mounted. The impeller shard is mounted off-center or eccentrically inside the hub, ie, the shaft is not cocentric with the centerline of the cylindrical hub in which the shaft is journalled. Furthermore, a narrow arc-shaped groove whose center line is concentric with the center line of the cylindrical hub is formed at the end of the rigid arm in which the driven member (centrifugal pump) is disposed. A single bolt passes through this arcuate slot and into a threaded hole formed in the pump housing.

When the endless belt is placed on a journal-supported drive belt wheel for rotation around the first end of the rigid arm and a follower wheel attached to the shaft of the pump impeller, the tension in the belt is , adjusted (within limits) by some simple loosening of a single bolt and then rotating the rigid arm around the hub of the pump as an axle.

When this is done, the distance between the centerlines of the drive and driven shafts is either increased or decreased depending on the direction of rotation of the arm. When the rigid arm is rotated in the first direction, an eccentricity is added to the distance between the drive shaft and the driven shaft, so that when the rigid arm is rotated in the opposite direction, the eccentricity is subtracted from the distance.

Once the desired tension is established, it is only necessary to re-secure the single bolt that fastens the rigid arm to the pump housing.

Furthermore, a feature of the present invention is that the two half-shifts are driven by a belt drive;
oriented together around the trailing vehicle and the belt connecting the two, consisting in the inclusion of a symmetrical shroud arrangement in which the two halves are bolted one to the other and to the rigid arm. . In addition to overall system safety, the shroud actually provides overall protection for any moving parts. Furthermore, it should be noted that the tension of the endless belt may be adjusted with a positioned shroud. The pump can also be easily removed for repair by removing the single bolt used to tighten the pump to the arm, and due to the lack of slippage of the endless belt.

The foregoing features and advantages of the present invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments, particularly when considered in the accompanying drawings in which like numerals in the several drawings relate to corresponding parts. It will become clearer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1, the belt drive system of the present invention is generally designated by the numeral 10.

It is shown to include a drive sheave 12 keyed to a stepped cylindrical stub shaft 14. The stub shaft 14 has an inwardly extending hole 16 and regularly spaced recesses 1 within the hole adapted to receive splines on a splined drive shaft (not shown).
8 is milled. - A tightening collar 20 surrounds the end portion of the grooved hole in the stub shaft 14,
A tightening collar is the subject of U.S. Pat. No. 4,185,938 to Pareja, also assigned to the designated assignee of this invention. As stated in that patent,
Only moderate pressure on the set screw 22 applies a relatively high force to prevent the drive shaft from loosening in the spline hole 16. The stepped stub shaft 14 has an integrally formed cylindrical projection 24 that fits within a suitable thrust-type ball bearing assembly 26, which assembly is attached to the rigid arm member 3.
2 is housed within a hole 28 formed in the first end 30 of 2. In this way, the pulley 12 and its stub shaft 1
4 is adapted to rotate freely relative to the rigid arm member 32. Grease cap 31 is held in place by retaining ring 33 and seals the bearing from external conditions.

Furthermore, the cylindrical hole 34 is formed at the lower end (as viewed in FIG. 1) of the thickness of the arm 32. The longitudinal axis of this hole is parallel to the axis of the stub shaft 14 when journaled within the bearing 26.

With continued reference to FIG. 1, the driven machine is generally designated by the numeral 36 and includes, for example, an impeller (not shown) keyed to and rotatable with the driven shaft 42 of the pump. ) may include a centrifugal pump having a housing 40 surrounding it. The shaft 42 is
The journal is journalled in a suitable bearing (also not shown) housed within a cylindrical hub portion 44 of pump housing 40. The diameter of the hub 44 is such that it fits slidingly within the hole 34 formed in the lower end of the rigid arm 32, and thus the arm can be rotated about the hub as its center. It is now possible to do this. However, the pump shaft 42 is journalled within the hub 44 such that the hub centerline 48 and the shaft 42 centerline 46 are designated as spaced apart centerlines.

As best shown in FIG.
1 is provided, and an arched slot 50 extends completely through the thickness of the flange, with a notch of approximately 90 mm.
It defines the angle of degree. The tightening bolt 56 is
It passes through the washer 52 and the narrow groove 50 and enters a threaded hole 54 formed in the pump housing 40 .

Tightening bolts 56 include only the means for securing the pump to rigid arm 32.

A follower wheel 58 is attached to the shaft of the pump, and an endless belt 60 connects the drive belt pulley 12 to the follower wheel 58. The drive belt is rotated in the counterclockwise direction when arm 32 is shown in FIG. 2, and the eccentricity between hub 44 and shaft 42 is subtracted from the overall distance between the centers of shafts 42 and 14. When the belt is selected to fit loosely over the edge flange of each pulley.

Then, when the arm is again rotated in the clockwise direction as shown in FIG. added to the distance, thus causing the belt to be in tension. When the desired degree of tension is applied to the belt, the bolt 56
6 is loosened to hold the arm fixed relative to the pump housing and maintain the preset belt tension.

As directed in the previously referenced Patent No. 3.863.517 to Pareja, the pump itself is equipped with a chain or other suitable accessory device (
The pump and arm may be latched to the frame by a motor (not shown), thus preventing the pulley 12 from turning suddenly as it is driven by its associated prime mover (not shown).

The drive mechanism, including drive sheave 12, belt 60, and follower sheave 58, is enclosed within a removable shroud, designated generally by numeral 62 in FIG. The shroud is a two piece assembly including a left half member 64 and a right half member 66. These two half holidays are
Generally oriented together to cover the moving parts of the drive system, the two halves are secured together by bolts as at 68 and 70 and secured as at 72 of the rigid arm 32.

When shaped like this, the tightening bolt 56 is
It is known that it is loosened and exposed so that the belt tension can be adjusted and the shroud pulled again without having to be removed to do so. This feature is added for overall safety considerations in that the operator does not attempt to remove the shroud while the pump is running.

The present invention provides those skilled in the art with the information necessary to comply with patent law and apply novel principles, and is hereby eminently distinguished for the construction and use of such specified compliments as required. It was explained in detail.

It is understood, however, that the invention may be carried out with particular and different equipment and equipment, and that various changes, both in terms of equipment details and operating procedures, may be made without departing from the scope of the invention as claimed in its own right. It should be.

[Brief explanation of the drawing]

FIG. 1 is a side view, partially in section, illustrating features of the invention; and FIG. 2 is a front view, with a portion of the shroud broken away for ease of viewing. 10... Belt drive system 12... Drive belt pulley 14... Stepped cylindrical stub shaft 16...
... Inwardly extending hole 32 ... Rigid arm member 36 ... Driven machine 40 ... Housing 42 ... Driven shaft 44 of the pump・・・・・・
...Cylindrical hub portion 46.48 ... Center line 50 ... Arch-shaped narrow groove 56 ... Tightening bolt 58 ... Follower wheel 60 ... ... Endless belt 62 ... Shroud.

Claims (4)

[Claims] (1) In a mechanical drive system in which a drive sheave is connected to a follower sheave by a flexible endless belt, a device for adjusting the tension of such belt is: (a) centered on a first axis; Formed in one piece,
a machine housing including a stationary cylindrical hub portion; (b) a first cylindrical shaft having a longitudinal centerline journalled for rotation in the cylindrical hub of the housing; (c) a first pulley fixed to the first shaft;
d) a rigid arm member having first and second parallel and spaced holes therethrough, said first hole receiving said cylindrical hub portion of said housing therein; (e) a rigid arm member having a diameter that is received in a predetermined sliding fit therebetween so that the rigid arm can be rotated about the hub to a desired angular position; a second shaft journalled for rotation in a hole in the shaft; (f) a second pulley attached to said second shaft; (g) a flexible member connecting said first and second pulleys; (h) a device comprising an arcuate groove of constant radius formed through the arm, the center of curvature of the arcuate groove being concentric with the first axis of the hub; and a tightening bolt passes through the slot and into a threaded hole in the housing that attaches the machine to the arm and adjustably fixes the angular position of the arm to the cylindrical hub portion of the housing. A device for adjusting the tension of a belt in a drive system of a belt and drive belt wheel, comprising: a device comprising; (2) An apparatus according to claim 1, in which the machine includes a centrifugal pump, and a belt tension adjustment device in a belt and drive belt pulley drive system. (3) A belt tension adjustment device in a belt and drive belt sheave drive system, further comprising a device for coupling said second pulley to a rotatable drive shaft. (4) In the device according to claim 1, the device is further attached to the rigid arm member, and the tightening bolt is left exposed, but generally the first pulley, the second pulley A belt tension adjustment device in a belt and drive belt pulley drive system including a pulley and a shroud member surrounding the endless belt.